Invariant agreement attraction effects: Distance and RC modification manipulations in Czech

Agreement attraction in comprehension often manifests itself as a speed-up in the of processing ungrammatical sentences where a verb carries the wrong number feature when a noun of the verb-matching number —the attractor—intervenes. The effect has been claimed to be insensitive to increased linear distance between the attractor and the agreement target. Recent studies on Czech found weak attraction effects attested only with case syncretic attractors. In two self-paced reading experiments with Czech comprehenders, we tested whether including material between the attractor and the verb could modulate attraction depending on whether the material was reinforcing the attractor's features or not. In Experiment 1, we aimed to increase attraction strength by modifying the attractor with a relative clause, giving it the subject feature and reinforcing its plurality. In Experiment 2, we matched the increased distance employed in Experiment 1 with feature-inert material to see if attraction was maintained. Our Bayes factor analysis provided us with evidence of a small attraction effect in the both experiments that did not differ meaningfully between the two. We therefore show that Czech exhibits online number attraction but of a tiny effect size. Our results further replicate earlier findings that distance does not affect agreement attraction in comprehension, as our effect sizes were comparable between the two experiments as well with previous work on Czech. Finally, they show that modifying attractors with relative clauses does not increase the strength of attraction speed-ups.